Refrigeration



May 20, 194 B. c. SHIFMAN REFRIGERATION Filed NOV. 19, 1938 6 r 2INVENTQR. I

ATTORNEY.

Patented May 20', 1941 REFRIGERATION Bennet Carroll Shipman, deceased,late of Arlington County, Va., by Clara Wood Shipmau, executrix,Birmingham, Ala., assignor to Servel, Inc., New York, N. Y., acorporation of Delaware Application November 19, 1938, Serial No.241,372

4 Claims.

This invention relates to refrigeration and it is an object of theinvention to provide for heat transfer from a plurality of refrigeratorsto a source of refrigeration located at a lower level.

The drawing shows a refrigeration transfer system embodying theinvention. At an upper level, for instance, the business floor of a meatmarket, delicatessen, restaurant, or like establishment, are threerefrigerators, a large walk-in type cooler III, a display case II, and asmall cooler I 2. In the upper part of walk-in cooler I6 is a coolingcoil I3 provided with a header I4. In the display case II is a coolingcoil I5 provided with a header or accumulator I6. In the smallrefrigerator I2 is a cooling coil l1 provided with a header oraccumulator l8. At a lower level, for instance, the basement of thestore, is a refrigeration apparatus of which only the evaporator I6 isillustrated. The refrigeration apparatus may be like that described inapplication Serial No. 107,852 of Albert R. Thomas.

In the evaporator I9 is a coil 26 which will be referred to as acondenser coil. Above the coil is a liquid distributor 22. Liquidrefrigerant enters evaporator I3 through a conduit 23. The liquid entersthe distributor 22 and thence is distributed onto the top of the coil26. The liquid descends over the outer surface of coil 20, evaporatingand diffusing into inert gas in the evaporator, producing arefrigerationeffect for cooling fluid on the inside of coil 26. Inert gas enters theupper part of evaporator I9 through conduit 24 and tube 25. The mixtureof gas and vapor leaves the lower part of the evaporator through conduit26.

Above the walk-in. cooler III is a separating vessel 21. The bottom ofvessel 21 is connected by a conduit 28.to the lower part of header I4.The top of vessel 21 is connected by a conduit 23 to the upper end ofcondenser coil 26. The lower end of condenser coil 26 is connected by aconduit 30 to the lower part of a vapor lift vessel 3I. The upper partof vessel 3| is connected by a conduit 32 to an intermediate part ofseparation vessel 21. The conduit 33 is connected by a T 33a to theupper part of conduit 32. The other end of conduit 33 is connected tobranch conduits 34' and 35.. Conduit 34 is connected to the lower partof header I6 in the display case II. Conduit 35 is connected to thelower part of header I8 in the small refrigerator l2.

nozzle 36. The nozzle 36 is connected in parallel to the headers I4, I6and I8 by a conduit 31 and branching conduits 38, 39, 40 and H. Conduit38 is connected to the upper part of header I4. Conduit 40 is connectedto the upper part of header I6. Conduit M is connected to the upper partof header I8.

In conduit 34 there is a control valve 42 similar to an expansion valve.Valve 42 is thermostatically operated responsiveto temperature at thethermostat bulb '43 which is in thermal contact with conduit 46 adjacentheader I6. A similar thermostatic valve 44 in conduit 35 operatesresponsive to temperatureat bulb 45 attached to conduit 4I adjacentheader l8.

The above described system is evacuated and charged with a suitable heattransfer fluid such as methyl chloride. When the refrigeration apparatusin the basement is started, the evaporator I9 reduces the temperature ofcondenser coil 26 so that vapor condenses to liquid in this coil andflows downward into conduit 30, vessel 3|, and the lower parts ofconduits 32 and 31. Collapse of vapor in coil 20 causes a reduction inpressure in conduit 29, separation vessel 21, and the upper end ofconduit 32. Due to the pressure difference in the system brought aboutby the reduction in pressure in said parts, vapor in conduit 31 at thehigher pressure forces liquid downward in the lower part of conduit 31until the vapor issues from nozzle 36. This vapor bubbles into liquid invessel 3i and rises in conduit 32. Liquid is carried upward by vapor inconduit 32 and vapor and liquid issue from the upper end of conduit 32in separation vessel 21. Liquid also enters conduit 33 at the T 33a andfills conduit 33 and branch conduits 34 and 35. The vapor flows fromseparation vessel 21 through conduit 29 back to the condenser coil 20.Liquid flows from separation vessel 21 through conduit 28 into header I4and cooling coil I3 in the walk-in cooler I0. Liquid flows from conduit34 into header I6 and coil I5 in the display case II. Liquid flows fromconduit 35 into header [8 and coil I1 in the small refrigerator I2. Inthe several coils I3, l5 and I1, liquid evaporates to produce cooling ofthe several refrigerators. The resulting vapor flows through thepreviously described vapor con duits into conduit 31 and thence to thenozzle 36 in the vapor lift vessel 3|.

In operation of the system, a column of liquid stands in conduit 33 at aheight H above the nozzle 36. This column of liquid is kept suppliedfrom the condenser coil 26. Conduit 32 contains a column of gas andliquid. This col- The valves 42 and 44 are constructed to move,

umn goes upward as liquid is supplied to conduit 30 and gas issues fromnozzle 36 so'that gas and liquid issue from the upper end of conduit 32.In conduit 28 and separation vessel 21, there stands a column'of liquidH1 above the surface level of liquid in header It. The apparatus isconstructed so that H1 can be equal to or slightly greater than H. Theseliquid columns may be referred to as reaction heads for the vapor liquidlift column 32. A column of liquid also stands in conduit 33 above thesurface level of liquid in the header I8. This column should be at leastequal to column H1. The system should be constructed so that this columnmay be appreciably greater than Hi to provide extra head for causingflow through the valves 42 and 44. The liquid column in conduit 33 backsup to the toward their closed positions upon decrease in tern tions uponincrease in temperature. These valves control flow of liquid throughconduits 34 and 35 into the cooling coils l5 and I1 respectively. Thevalves 42 and 44 may be adjusted to maintain difierent temperatures inthe respective refrigerators.

Various changes may be made within the scope of the invention which isnot limited except as indicated in the following claims.

What is claimed is: V

1. In a method of heat transfer including evaporation of heat transferfluid at an upper level,

condensation of the fluid to liquid at a lower level, and raising liquidupward from said lower level, that improvement which-consists incarrying out evaporation at a plurality of upper levels, utilizingvapor-resulting from said evaporation to cause said raising of liquidupward from said lower level, conducting raised liquid rature and movtoward their-open posi-' to said upper levels by gravity flow, andcontrolling flow of liquid to a lower one of said upper levelsresponsive to a temperature condition affected by evaporation at thatlevel.

2. In a method of heat transfer including evaporation of heat transferfluid at an upper level,

condensation of the fluid to liquid at a lower level, and raising ofliquid between said'levels by means of vapor produced at the upperlevel, that improvement which consists in carrying out evaporation at aplurality of upper levels, causing said raising of liquid by vapor liftaction of vapor produced at said upper levels,'and utilizing'thedifference in said upper levels to form a liquid column to act againstthe pressure of vapor at a I lower one of said upper levels.

3. A circuit for heat transfer fluid including a place of condensation,a plurality of places of evaporation above said' place ,of condensation,vapor operated means for raising liquid upward from said place ofcondensation, conduit means for receiving in parallel vapor from saidplaces of evaporation and conducting the vapor to said liquid raisingmeans, and conduits vfor conducting raised liquid by gravity to saidplaces of evaporation in parallel and arranged toprovide. liquid columnsfor acting against the pressure of said vapor. 4.A circuit for heattransfer fluid including a place of condensation, a plurality ofplaces'of evaporation at difierent-levels abovesaid place ofcondensation, means operated by pressure of vapor inthe circuit forraising liquid upward fromsaid place of condensatiomgconduits forconducting raised liquid by gravity to said places of evaporation,

of said places of evaporation.

man, Deceased.

and temperature responsive meansfor controlling flow of liquid to alower

